Score manipulation,density continuity and intent-to-treat effect for regression discontinuity

Regression discontinuity (RD) is widely used in many disciplines of science to find treatment effect when the treatment is determined by an underlying running variable (‘score') crossing a cutoff or not. The main attraction of RD is local randomization around , which is, however, often ruined by manipulation on . To detect manipulation, the continuity of score density function at is routinely tested in practice. In this paper, we examine how informative is for RD, and show the following. First, for incumbency effect in election to which RD has been heavily applied, may have no information content. Second, for RD in general, the continuity is neither necessary nor sufficient for RD validity. Third, if the treatment cannot be implemented without manipulation of , then the manipulation had better be considered as part of the treatment effect, much as in ‘intent-to-treat effect’ for clinical trials. These findings call for relying less on continuity tests and, instead, thinking more about how subjects react to the treatment to modify their , how to design the treatment to lessen manipulation, and what to take as the desired treatment effect.     

Less timely earnings announcements and voluntary disclosure

The release of earnings information has become less timely in recent years partly because firms increasingly disclose earnings concurrently with their periodic reports (e.g., 10-Ks, 10-Qs). We examine whether firms use voluntary disclosure to mitigate the negative economic consequences of less timely earnings announcements (EAs). We find that firms with less timely EAs are more likely to provide voluntary 8-K filings over the period leading to the EA. We also find that investors’ demand for timely information, the nature of earnings news and litigation risk affect the extent to which firms provide voluntary disclosure to compensate for less timely EAs. The negative effect of less timely EAs on information asymmetry is attenuated when firms provide voluntary 8-K filings prior to EAs. Overall, our findings suggest that firms voluntarily communicate with investors using voluntary disclosure when their EAs are less timely.